How to output java -jar errors to a text/log file?

Question

i have googled my heart out! I am trying to figure out how to output any errors a java class might give when executing java from the Windows command line.

For instance

java -jar class.jar <someFile.file>

if that line throws any errors, i want them to be stored into a text file for later reviewing.

I tried

java -jar class.jar <someFile.file> >> log.txt

But despite throwing errors the log.txt file is empty.

Thanks all!

Answer 1

Use:

java -jar class.jar <someFile.file> 2>> log.txt

The 2 redirects the error stream.